chore: Update README to Clarify Wallet Hydration + Doc Links (#45)

* chore: Update README to Clarify Wallet Hydration + Doc Links

* typo

Author: John-peterson-coinbase

README.md

@@ -42,7 +42,9 @@ To start a Python REPL:
 python
 ```
 
-## Creating a Wallet
+## Quickstart
+
+### Creating a Wallet
 
 To start, [create a CDP API key](https://portal.cdp.coinbase.com/access/api). Then, initialize the CDP SDK by passing your API key name and API key's private key via the `configure` method:
 
@@ -69,7 +71,7 @@ print("CDP SDK has been successfully configured from JSON file.")
 
 This will allow you to authenticate with the Platform APIs.
 
-If you are using a CDP Server-Signer to manage your private keys, enable it with
+If you are using a CDP [Server-Signer](https://docs.cdp.coinbase.com/mpc-wallet/docs/serversigners) to manage your private keys, enable it with
 
 ```python
 Cdp.use_server_signer = True
@@ -91,7 +93,7 @@ Wallets come with a single default address, accessible via `default_address`:
 address = wallet1.default_address
 ```
 
-## Funding a Wallet
+### Funding a Wallet
 
 Wallets do not have funds on them to start. For Base Sepolia testnet, we provide a `faucet` method to fund your wallet with
 testnet ETH. You are allowed one faucet claim per 24-hour window.
@@ -106,7 +108,7 @@ faucet_tx.wait()
 print(f"Faucet transaction successfully completed: {faucet_tx}")
 ```
 
-## Transferring Funds
+### Transferring Funds
 
 See [Transfers](https://docs.cdp.coinbase.com/wallets/docs/transfers) for more information.
 
@@ -125,7 +127,7 @@ transfer = wallet1.transfer(0.00001, "eth", wallet2).wait()
 print(f"Transfer successfully completed: {transfer}")
 ```
 
-### Gasless USDC Transfers
+#### Gasless USDC Transfers
 
 To transfer USDC without needing to hold ETH for gas, you can use the `transfer` method with the `gasless` option set to `True`.
 
@@ -146,14 +148,14 @@ print(f"Faucet transaction successfully completed: {usdc_faucet_tx}")
 transfer = wallet1.transfer(0.00001, "usdc", wallet3, gasless=True).wait()
 ```
 
-## Listing Transfers
+### Listing Transfers
 
 ```python
 # Return list of all transfers. This will paginate and fetch all transfers for the address.
 list(address.transfers())
 ```
 
-## Trading Funds
+### Trading Funds
 
 See [Trades](https://docs.cdp.coinbase.com/wallets/docs/trades) for more information.
 
@@ -168,14 +170,68 @@ trade = wallet.trade(0.00001, "eth", "usdc").wait()
 print(f"Trade successfully completed: {trade}")
 ```
 
-## Listing Trades
+### Listing Trades
 
 ```python
 # Return list of all trades. This will paginate and fetch all trades for the address.
 list(address.trades())
 ```
 
-## Creating a Webhook
+### Re-Instantiating Wallets
+
+The SDK creates wallets with [Developer-Managed (1-1)](https://docs.cdp.coinbase.com/mpc-wallet/docs/wallets#developer-managed-wallets) keys by default, which means you are responsible for securely storing the keys required to re-instantiate wallets. The below code walks you through how to export a wallet and store it in a secure location.
+
+```python
+# Export the data required to re-instantiate the wallet. The data contains the seed and the ID of the wallet.
+data = wallet.export_data()
+```
+
+In order to persist the data for the wallet, you will need to implement a store method to store the data export in a secure location. If you do not store the wallet in a secure location you will lose access to the wallet and all of the funds on it.
+
+```python
+# You should implement the "store" method to securely persist the data object,
+# which is required to re-instantiate the wallet at a later time. For ease of use,
+# the data object is converted to a dictionary first.
+store(data.to_dict())
+```
+
+For convenience during testing, we provide a `save_seed` method that stores the wallet's seed in your local file system. This is an insecure method of storing wallet seeds and should only be used for development purposes.
+
+To encrypt the saved data, set encrypt to `True`. Note that your CDP API key also serves as the encryption key for the data persisted locally. To re-instantiate wallets with encrypted data, ensure that your SDK is configured with the same API key when invoking `save_seed` and `load_seed`.
+
+```python
+# Pick a file to which to save your wallet seed.
+file_path = "my_seed.json"
+
+# Set encrypt=True to encrypt the wallet seed with your CDP secret API key.
+wallet.save_seed(file_path, encrypt=True)
+
+print(f"Seed for wallet {wallet.id} successfully saved to {file_path}.")
+```
+
+The below code demonstrates how to re-instantiate a wallet from the data export.
+
+```python
+# You should implement the "fetch" method to retrieve the securely persisted data object,
+# keyed by the wallet ID.
+fetched_data = fetch(wallet.id)
+
+# imported_wallet will be equivalent to wallet.
+imported_wallet = Wallet.import_data(fetched_data)
+```
+
+To import Wallets that were persisted to your local file system using `save_seed`, use the below code.
+
+```python
+# Get the unhydrated wallet from the server.
+fetched_wallet = Wallet.fetch(wallet.id)
+
+# You can now load the seed into the wallet from the local file.
+# fetched_wallet will be equivalent to imported_wallet.
+fetched_wallet.load_seed(file_path)
+```
+
+### Creating a Webhook
 A webhook is a way to provide other applications with real-time information from the blockchain. When an event occurs on a blockchain address, it can send a POST request to a URL you specify. You can create a webhook to receive notifications about events that occur in your wallet or crypto address, such as when a user makes a transfer.
 ```python
 from cdp.client.models.webhook import WebhookEventType
@@ -189,7 +245,7 @@ wh1 = Webhook.create(
 print(wh1)
 ```
 
-## Creating a Webhook On A Wallet
+### Creating a Webhook On A Wallet
 A webhook can be attached to an existing wallet to monitor events that occur on the wallet, i.e. all addresses associated with this wallet. A list of supported blockchain events can be found [here](https://docs.cdp.coinbase.com/get-started/docs/webhooks/event-types).
 ```python
 import cdp
@@ -199,6 +255,9 @@ wh1 = wallet1.create_webhook("https://your-app.com/callback")
 print(wh1)
 ```
 
+## Examples
+Examples, demo apps, and further code samples can be found in the [CDP SDK Python Documentation](https://docs.cdp.coinbase.com/cdp-apis/docs/welcome).
+
 ## Contributing
 
 See [CONTRIBUTING.md](CONTRIBUTING.md) for more information.